19 April 2012

Dementia is a loss of brain function that occurs with certain diseases. Alzheimer's disease (AD), is one type of dementia that gradually gets worse over time. It affects memory, thinking, cognition, and behavior.

Alzheimer's disease (AD) is a progressive brain disease that destroys memory and cognitive skills by damaging the normal and healthy functions of the brain.

AD is caused when protein fragments called plaques and tangles stick together to form the Alzheimer's protein. This protein then starts to kill brain cells starting at the hippocampus and ultimately destroying the whole brain (See video).

Get moving: Daily exercise may reduce Alzheimer's disease risk at any age

Daily physical exercise may reduce the risk of Alzheimer's disease, even in people over the age of 80, according to a study published in the online issue of Neurology®, the medical journal of the American Academy of Neurology.

"The study showed that not only exercise but also activities such as cooking, washing the dishes and cleaning are associated with a reduced risk of Alzheimer's disease," said study author Aron S. Buchman, MD, with Rush University Medical Center in Chicago and a member of the American Academy of Neurology. "These results provide support for efforts to encourage physical activity in even very old people who might not be able to participate in formal exercise but can still benefit from a more active lifestyle."

For the study, a group of 716 people with an average age of 82 wore an actigraph, a device that monitors activity, on their non-dominant wrist continuously for 10 days. All exercise and non-exercise was recorded. They also were given annual tests during the four-year study that measured memory and thinking abilities. During the study, 71 people developed Alzheimer's disease.
Video: What is Alzheimer's Disease?

Participants also self-reported their physical and social activity. Buchman said this is the first study to use an objective measurement of physical activity in addition to self-reporting. "This is important because people may not be able to remember the details correctly," he said.

The research found that people in the bottom 10 percent of daily physical activity were more than twice as likely to develop Alzheimer's disease as people in the top 10 percent of daily activity.

The study also showed that those people in the bottom 10 percent of intensity of physical activity were almost three times as likely to develop Alzheimer's disease as people in the top 10 percent of intensity of physical activity.

"Since the actigraph was attached to the wrist, activities like cooking, washing the dishes, playing cards and even moving a wheelchair with a person's arms were associated with a lower Alzheimer's risk," said Michal Schnaider-Beeri, PhD, of Mount Sinai School of Medicine in New York in an accompanying editorial. "These are low-cost, easily accessible and side-effect free activities people can do at any age, including very old age, to possibly prevent Alzheimer's disease."